Not the same at all (but I don't book award travel often and it's the only example I have) but:
I was able to book 2xCW seats BOS-LHR and LHR-BOS back in December 2010 for travel this August. Well under a year in advance and surely a more popular date (and I remember having a choice of dates too) albeit on a shorter route that may have more flights per day (BOS has 3 daily).